Can crops achieve high yields only with heavy potassium fertilizer application? Explanation of rational application methods
When it comes to fertilizers, there is no such thing as one fertilizer being good and another being bad, but among fertilizers, potassium fertilizer is indeed a rather special case, so can crops achieve high yields only with heavy potassium fertilizer application? How should it be applied rationally?
1. What role does potassium fertilizer play? Can it increase yield?
1. Improving stress resistance
During plant growth, potassium participates in numerous physiological activities. It can promote the metabolism of carbohydrates and nitrogen, control and regulate the activity of various mineral nutrient elements, activate the activity of various enzymes, control the transport of nutrients and water, and maintain the internal pressure of cells, thereby preventing plants from wilting.
2. Improving quality
Applying potassium fertilizer can improve the stress resistance of crops and plays a very important guaranteeing role in high and stable crop yields. For example, with corn, applying potassium fertilizer can improve the quality of corn stalks and prevent lodging.
3. Increasing yield
Because the original soil in some areas has a relatively high potassium content, many farmer friends have not yet realized the important effect of potassium on yield.
2. How should potassium fertilizer be applied rationally?
1. Common types of potassium fertilizer
(1) Potassium sulfate
White or light yellow crystals, soluble in water, with little hygroscopicity. It can be used as a base fertilizer or a topdressing fertilizer and is suitable for various crops, especially chlorine-sensitive and potassium-loving crops, and should be applied in a properly concentrated manner.
(2) Potassium nitrate
White powder or crystals, soluble in water, with little hygroscopicity.
(3) Potassium dihydrogen phosphate
Colorless to white crystals or crystalline powder, soluble in water, stable in air. At present, it is mostly used for seed soaking and foliar topdressing.
(4) Biological potassium fertilizer
It can be used for seed dressing, root dipping, or applied into the soil. Applying microbial inoculants is actually inoculating the crop root system, allowing silicate bacteria to release potassium, phosphorus, silicon, iron and other elements in the soil around the roots for the root system to absorb and utilize.
2. Under what circumstances should potassium fertilizer be applied?
(1) Look at the soil
The potassium content in China's soils is gradually decreasing. In addition, potassium fertilizer should be applied in appropriate amounts to northern soils.
(2) Look at the crop
Because potassium plays an important role in increasing the protein and sugar content of crops, potassium fertilizer is generally recommended for cash crops, especially legumes, tuber crops, cotton and flax, tobacco, and fruit trees.
(3) Look at external nutrient inputs
In recent years, returning straw to the field has been advocated because straw has a relatively high potassium content and releases it easily, and can supply a large amount of potassium to the soil.
3. Precautions for applying potassium fertilizer
(1) Apply according to the soil
Potassium fertilizer should first be applied to areas where the soil is severely deficient in potassium. From the perspective of soil texture, sandy soil often has a relatively low content of available potassium, so potassium fertilizer should be increased; clayey soil often has a relatively high content of available potassium, so it can be applied less or not at all. For soil deficient in both potassium and sulfur, potassium sulfate can be applied, while potassium chloride must not be applied to saline-alkali land.
(2) Apply according to the crop
In rainy areas or areas with irrigation conditions and good drainage, most crops can be given potassium chloride, while a small number of cash crops should not be given potassium chloride in order to improve quality.
(3) Reasonable combination
For tobacco, sugar crops and fruit trees, potassium sulfate is the better choice; because potassium sulfate is relatively costly, potassium sulfate can be chosen for high-efficiency cash crop fields, while for general field crops, except for a small number of chlorine-sensitive crops, the cheaper potassium chloride is preferable.